Characterization and Evaluation of 2-Methylene-13,6-Trioxocane (MTC) Hydrogels As a Biomaterial for Tissue Engineering and Drug Delivery Applications

The three-dimensional (3D), cross-linked network structure of gels and hydrogels and their generally hydrophilic nature make gels/hydrogels suitable for use in biomaterials applications, including for tissue engineering and drug delivery purposes. In this work, a novel gel/hydrogel material is presented for use as a tissue engineering support or scaffolding material as well as as a drug delivery vehicle. 2-methylene-1,3,6-trioxocane (MTC), which was first synthesized decades ago as a monomer and is largely more hydrophobic in nature, is polymerized and cross-linked for the first time through the use of poly(ethylene glycol) diacrylate (PEGDA). By varying the length of PEGDA crosslinker and taking advantage of the unique polymerization of MTC through radical ring-opening polymerization (RROP) that introduces the degradability into the polymer, tunable gels/ hydrogels are fabricated and characterized for potential use as a biodegradable tissue engineering scaffold and for the delivery of various characteristic drugs (small molecule hydrophobic/ hydrophilic drugs and larger protein). Based on the amount of crosslinker and the degree of crosslinking properties such as the rheological mechanics, degree of swelling, rate of degradation, and drug release profiles show distinct differences. Because of this, the ideal gels/ hydrogels for tissue engineering are evaluated for cell seeding and in vivo application. The distinct properties of MTC as a hydrogel not only make it a suitable material for tissue engineering but also allows for facile sugar porogen processing that is not possible with traditional hydrogel material. Likewise, the utility of MTC hydrogels to deliver small and large molecules at different rates is discussed and the injectability of the subsequently crosslinked material is assessed for future in vivo applications. The characterization of MTC for various applications is thoroughly studied in this work and sets the stage for use as a superior biocompatible, biodegradable gel/ hydrogel.